const grpc = require("@grpc/grpc-js")
const message_proto = require("./proto")
const const_module = require("./const")
const {v4:uuidv4} = require("uuid")
const emailModule = require("./email")
const configModule = require("./config")
const redis_module = require('./redis')


async function GetVerifyCode(call, callback) {
    console.log("email is ", call.request.email)
    try{
        let query_res = await redis_module.GetRedis(const_module.code_prefix + call.request.email)
        console.log("query_res_code is ", query_res)
        let uniqueId = query_res
        if(query_res == null) {
            uniqueId = uuidv4()
            if(uniqueId.length > 4) {
                uniqueId = uniqueId.substring(0, 4)
            }
            // 600s 过期时间
            let bres = await redis_module.SetRedisExpire(const_module.code_prefix + call.request.email, uniqueId, 600)
            if(!bres) {
                callback(null, { email:  call.request.email,
                    error:const_module.Errors.RedisErr
                }); 
            }
            return;
        }
        
        console.log("uniqueId is ", uniqueId)
        let text_str =  '您的验证码为'+ uniqueId +'请三分钟内完成注册'
        //发送邮件
        let mailOptions = {
            from: configModule.email_user,
            to: call.request.email,
            subject: '验证码',
            text: text_str,
        };

        let send_res = await emailModule.SendMail(mailOptions);
        console.log("send res is ", send_res)

        callback(null, { email:  call.request.email,
            error:const_module.Errors.Success
        }); 


    }catch(error){
        console.log("catch error is ", error)

        callback(null, { email:  call.request.email,
            error:const_module.Errors.Exception
        }); 
    }

}

function main() {
    var server = new grpc.Server()
    server.addService(message_proto.VerifyService.service, { GetVerifyCode: GetVerifyCode })
    server.bindAsync(configModule.server_host + ":" + configModule.server_port, grpc.ServerCredentials.createInsecure(), () => {
        server.start()
        console.log('grpc server started: ' + configModule.server_host + ":" + configModule.server_port)        
    })
}

main()